Sliding mode control (SMC) is a widely used control law for quadrotor regulation and tracking control problems. The purpose of this article is to solve the tracking problem of quadrotors using a relatively novel nonlinear control law based on SMC that makes use of a conditional integrator. It is demonstrated by a motivation example that the proposed control law can improve the transient response and chattering shortcomings of the previous approaches of similar SMC based controllers. The adopted Newton–Euler model of quadrotor dynamics and controller design is treated separately in two subsystems: attitude and position control loops. The stability of the control technique is demonstrated by Lyapunov’s analysis and the effectiveness and performance of the proposed method are compared with a similar integral law, also based on SMC, and validated by tracking control problems using numerical simulations. Simulations were developed in the presence of external disturbances in order to evaluate the controller robustness. The effectiveness of the proposed controller was verified by performance indexes, demonstrating less accumulated tracking errors and control activity and improvement in the transient response and disturbance rejection when compared to a conventional integrator sliding mode controller.

Heavy fuel oil (HFO) is a widely used fuel in compression ignition engines, primarily in Brazilian thermoelectric plants, mainly due to its availability, low cost, and low operational expenses. However, heavy fuel oil is not compatible with most diesel engines and combustion systems in use and must be treated to maintain combustion process efficiency. The high viscosity of heavy fuel oil must be reduced before being introduced into the engine. To achieve this, appropriate heating devices are added to the fuel lines, with steam being the primary working fluid in these devices. Steam-generating boilers that burn fossil fuels, including HFO itself, are the most viable option from an economic standpoint and in terms of utilizing locally available fuels for this function. However, the need to mitigate the effects of environmental pollution has encouraged the adoption of other types of boilers, such as electric ones. In this work, a case study of a combustion steam generator installed in a Brazilian thermoelectric plant is developed. This study involves the thermodynamic and combustion modeling of the steam generator through the balancing of the respective thermodynamic and combustion equations. The models and the proposed chemical formula of HFO were validated, and through simulations using real data collected during the boiler’s operation throughout 2024, it was also possible to estimate the carbon dioxide emissions produced. Additionally, a hypothetical scenario was simulated in which the combustion boiler currently installed in the plant is replaced by two electric boilers. A simple economic analysis demonstrated that such a replacement would result in a total steam production cost of only 25% of the amount spent on the current combustion boiler, in addition to reducing $C{O}_2$ emissions to the atmosphere by 62.55 tons.